多普勒组织成像评价房间隔缺损并肺动脉高压患者右心室舒张功能

目的探讨多普勒组织成像(DTI)技术评价房间隔缺损(ASD)并肺动脉高压患者右心室舒张功能的临床意义.方法56例ASD并肺动脉高压患者按肺动脉高压程度分为轻、中、重3组,并选取22例健康人作为正常对照组.采用频谱多普勒技术分别测定三尖瓣口舒张早期血流峰值速度e波、舒张晚期血流峰值速度a波,并计算e/a比值.然后进入DTI条件,测定三尖瓣环舒张早期运动峰值速度E波、舒张晚期运动峰值速度A波,并计算E/A比值.结果ASD并肺动脉高压患者右心室舒张功能随肺动脉压力的升高而逐渐减低;与频谱多普勒检测三尖瓣口充盈参数法相比,DTI法在ASD并轻、中度肺动脉高压患者中,对右心室舒张功能异常检出率更高,而在重度肺动脉高压患者中两者无差别.结论DTI在早期检测ASD并肺动脉高压患者右心室舒张功能减低方面较频谱多普勒具有优越性,其不但能早期预测病情变化,且可以帮助判断病情变化程度.     

In Vivo Lateral Blood Flow Velocity Measurement Using Speckle Size Estimation

In previous studies, we proposed blood measurement using speckle size estimation, which estimates the lateral component of blood flow within a single image frame based on the observation that the speckle pattern corresponding to blood reflectors (typically red blood cells) stretches (i.e., is “smeared”) if blood flow is in the same direction as the electronically controlled transducer line selection in a 2-D image. In this observational study, the clinical viability of ultrasound blood flow velocity measurement using speckle size estimation was investigated and compared with that of conventional spectral Doppler of carotid artery blood flow data collected from human patients in vivo. Ten patients (six male, four female) were recruited. Right carotid artery blood flow data were collected in an interleaved fashion (alternating Doppler and B-mode A-lines) with an Antares Ultrasound Imaging System and transferred to a PC via the Axius Ultrasound Research Interface. The scanning velocity was 77 cm/s, and a 4-s interval of flow data were collected from each subject to cover three to five complete cardiac cycles. Conventional spectral Doppler data were collected simultaneously to compare with estimates made by speckle size estimation. The results indicate that the peak systolic velocities measured with the two methods are comparable (within ±10%) if the scan velocity is greater than or equal to the flow velocity. When scan velocity is slower than peak systolic velocity, the speckle stretch method asymptotes to the scan velocity. Thus, the speckle stretch method is able to accurately measure pure lateral flow, which conventional Doppler cannot do. In addition, an initial comparison of the speckle size estimation and color Doppler methods with respect to computational complexity and data acquisition time indicated potential time savings in blood flow velocity estimation using speckle size estimation. Further studies are needed for calculation of the speckle stretch method across a field of view and combination with an appropriate axial flow estimator.     

How should we measure left atrium size and function?

Echocardiographic assessment of left atrial size from M-mode or 2D echocardiography measurements has been used in clinical and research studies for years, but its accuracy is now questioned. New techniques, such as 3D and tissue Doppler imaging, assessing velocities, strain and strain rate, provide improved prognostic value in a wide range of diseases. 2D strain imaging using speckle tracking on B-mode images may yield even better, angle-independent, results than tissue Doppler imaging-derived strain echocardiography. Finally, velocity vector imaging is a novel image analysis technique that may be used to quantify left atrial volume.     

超声心动图对伴肺动脉高压的房间隔缺损患者右心室功能的研究

目的 探讨右心室Tei指数检查伴肺动脉高压的房间隔缺损患者右心室功能的价值.方法 伴不同程度肺动脉高压的房间隔缺损患者28例,正常对照组33例,分别采用脉冲波多普勒成像和组织多普勒成像技术测算右室Tei指数1和Tei指数2.结果 伴不同程度肺动脉高压的房间隔缺损患者右心室Tei指数1、Tei指数2均明显大于正常对照组（P＜0.01）;伴中重度肺动脉高压房间隔缺损患者的右心室Tei指数1 、Tei指数2均大于伴轻度肺动脉高压房间隔缺损的患者;正常对照组、房间隔缺损组右心室Tei指数2与Tei指数1均呈正相关（P＜0.01）.结论 伴肺动脉高压的房间隔缺损患者存在不同程度的右室功能降低;右室Tei指数能较全面准确地评价右心室功能;而由组织多普勒脉冲法获取的右心室Tei指数更简便、易行,且准确性高,是对传统血流多普勒方法的改进和有益补充.     

彩色多普勒检测肺动脉血流对诊断室间隔缺损部位的临床价值

目的探讨用彩色多普勒血流显像检测肺动脉的血流速度,对判断不同类型的室间隔缺损的临床价值。方法对经手术证实的76例先天性室间隔缺损患者,按缺损部位分为A、B两组。按缺损大小分为C、D两组。用彩色多普勒超声测量各房室内径、肺动脉内径、肺动脉收缩期的最大血流速度、室间隔缺损大小、室间隔缺损处左向右的最大分流速度。结果A组和B组在左房室内径、肺动脉内径无明显差异(P>0.05),肺动脉收缩期最大血流速度,两组有明显差异(P<0.05)。C组和D组在左房室内径、肺动脉内径、肺动脉血流速度有明显差异(P<0.05),室间隔分流速度无明显差异(P>0.05)。结论肺动脉收缩期最大血流速度对诊断室间隔小缺损的部位有一定的辅助作用。     

房间隔缺损封堵术后右心血流动力学改变

目的观察房间隔缺损封闭后右心血流动力学的变化.方法 25例成年继发孔房间隔缺损患者,术前、术后48～72 h及3个月后经胸超声心动图检查,测量缺损、三尖瓣及肺动脉瓣瓣口血流多普勒及三尖瓣前叶瓣环运动的组织多普勒频谱.结果术前测量缺损平均直径约(2.2±0.6)cm,均成功植入封堵器.术后早期右心收缩期运动速度减低、时间缩短,血流峰值速度及压差降低、射血时间缩短;右房、室间压差降低.3个月后以上参数较术后早期无显著差异,但右室舒张时间延长.结论右心前负荷的降低短期内使右心肺循环高动力状态逆转,在新的前负荷水平达到新平衡.     

Doppler atrial shunt flow patterns in patients with secundum atrial septal defect: determinants, limitations, and pitfalls

Fifteen patients with uncomplicated secundum atrial septal defect underwent studies with real-time color-coded two dimensional flow imaging, pulsed Doppler echocardiographic examination, and simultaneous pressure recordings from the left and right atrium to determine the flow-pressure dynamics of the atrial shunt flow. In all 15 patients both the color flow mapping and pulsed Doppler studies revealed that the shunt flow was mainly from left to right, occurring both during ventricular systole and diastole. It started in early systole, reached a peak in late systole to early diastole, and lasted throughout diastole with an accentuation in late diastole during atrial contraction. The amplitude of the flow velocity, the direction, and the magnitude of the shunt flow, however, changed from phase to phase during the cardiac cycle. It correlated well with the phasic variation of the interatrial pressure difference, which usually revealed a peak pressure gradient that occurred in early systole between the x descent and v wave and during the period of v wave and a wave of the left atrial pressure tracing. Right to left shunt was not detected in any of the 15 patients by color flow mapping studies. A minor reversal of the shunt flow, however, was frequently detected at the beginning of ventricular systole and sometimes also in the middle of diastole by pulsed Doppler echocardiography. The reversal of shunt flow correlated with the minor reversal of pressure gradient that occurred during the z point, x descent, and y descent of the left atrial pressure tracing. In conclusion, left to right shunt flow occurs both during ventricular systole and diastole in uncomplicated secundum atrial septal defect.(ABSTRACT TRUNCATED AT 250 WORDS)     

Three-dimensional color Doppler echocardiography for assessing shunt volume in atrial septal defects.

Background Three-dimensional color Doppler echocardiography has been used to assess cardiac blood flow in experimental settings. We tested whether this technique can be applied to assess transatrial shunt flow in patients with atrial septal defect in a clinical setting. Methods In 46 consecutive patients with atrial septal defects, shunt flow was assessed during cardiac catheterization using the Fick method and by conventional 2-D quantitative transesophageal Doppler echocardiography. The averaged values for shunt flow obtained by both methods were used as a reference. Transesophageal 3-D color Doppler echocardiography was performed for analysis of the 3-D flow velocity field of transatrial shunt flow. Shunt volume was calculated by application of the Gauss theorem. Results We found a close correlation between shunt volume (L/min) obtained by either 3-D color Doppler echocardiography or the reference methods ( r = 0.981, P < .001). Using 3-D color Doppler data to predict the reference values, 95% confidence limits were -11.5 to +11.6%. Conclusions Shunt flow in patients with atrial septal defects can be assessed in a clinical setting by transesophageal 3-D color Doppler echocardiography.     

房间隔缺损时左房扩大的机理探讨

本文应用日本ＡｌｏｋａＳＳＤ－８６０及美国ＨＰＳＯＮＯＳ１０００彩色多普勒超声心动图诊断仪，对５０例被手术证实的房间隔缺损患者及１００例正常对照的左右心腔及大血管内径和血流频谱进行了系统观察，结果发现：房间隔缺损时不仅右心系统血容量增大，而且左房扩大，其左房的大小与心房水平的左向右分流量密切相关，ｒ＝０．８０７，与肺体循环血量相比，ｒ＝０．６１１，与房间隔缺损的大小相比，ｒ＝０．５１４。     

Analysis of athletes’ heart by tissue Doppler and strain/strain rate imaging

After regular and prolonged training, some physical and structural changes occur in the heart. Strain (S) imaging and Strain Rate (SR) imaging are new and effective techniques derived from tissue Doppler imaging (TDI) which examine systolic and diastolic functions. The aim of the present study was to evaluate left ventricular TDI and S/SR imaging properties in athletes and sedentary controls. The study population consisted of 26 highly trained athletes (group I) and age, sex and body mass index (BMI) adjusted 23 control subjects (group II) who had no pathological conditions. Using standard transthoracic and Doppler echocardiographical measurements and reconstructed spectral pulsed wave tissue Doppler velocities, the S/SR imaging of six different myocardial regions were evaluated. There was a significant increase in left ventricular systolic (LVSD) and diastolic (LVDD) diameter, inter-ventricular septum (IVS), left ventricular mass (LVm), left atrial diameter (LA), and transmitral Doppler peak E velocity (flow velocity in early diastole) between group I and group II in the case of echocardiographic findings. In athletes, TDI analysis showed a significantly increased mitral annulus lateral TDI peak early diastolic (E) velocity (18.8 ± 4.1 cm/s vs. 15 ± 3.5 cm/s, P < 0.01), septal TDI peak E velocity (15.8 ± 2.8 cm/s vs. 12.8 ± 2.4 P < 0.001). There were no significant differences in myocardial velocity imaging parameters between group I and group II. Peak systolic strain/strain rates of septal and lateral walls in group I were significantly higher than group II. This study demonstrates that left ventricular S/SR imaging was higher in athletes than in healthy subjects. In addition to traditional echocardiographic parameters, SI/SRI could be utilised as a useful echocardiographic method for cardiac functions of athletes.     

胎儿室间隔缺损的产前超声诊断

目的 :探讨超声心动图诊断胎儿室间隔缺损的临床价值。方法 :在胎儿左心长轴、四腔心切面重点观察室间隔有无中断 ,应用多普勒超声观察有无穿隔彩色血流和分流频谱 ,并多切面观察有无其他心内畸形。结果 :产前超声诊断胎儿室间隔缺损 2 7例 (单纯性 8例 ,伴其他畸形 18例 ,宫内自然闭合 1例 ) ,经引产尸体解剖证实 12例 ,产后超声检查证实 14例。结论 :二维超声是诊断胎儿室间隔缺损的重要方法 ,彩色与频谱多普勒超声具有辅助诊断价值     

Fast block flow tracking of atrial septal defects in 4D echocardiography

We are working to develop beating-heart atrial septal defect (ASD) closure techniques using real-time 3D ultrasound guidance. The major image processing challenges are the low-image quality and the processing of information at high-frame rate. This paper presents comparative results for ASD tracking in time sequences of 3D volumes of cardiac ultrasound. We introduce a block flow technique, which combines the velocity computation from optical flow for an entire block with template matching. Enforcing adapted similarity constraints to both the previous and first frames ensures optimal and unique solutions. We compare the performance of the proposed algorithm with that of block matching and region-based optical flow on eight in vivo 4D datasets acquired from porcine beating-heart procedures. Results show that our technique is more stable and has higher sensitivity than both optical flow and block matching in tracking ASDs. Computing velocity at the block level, our technique tracks ASD motion at 2 frames/s, much faster than optical flow and comparable in computation cost to block matching, and shows promise for real-time (30 frames/s). We report consistent results on clinical intra-operative images and retrieve the cardiac cycle (in ungated images) from error analysis. Quantitative results are evaluated on synthetic data with maximum tracking errors of 1 voxel.     

Flow Velocity Mapping Using Contrast Enhanced High-Frame-Rate Plane Wave Ultrasound and Image Tracking: Methods and Initial in Vitro and in Vivo Evaluation

Ultrasound imaging is the most widely used method for visualising and quantifying blood flow in medical practice, but existing techniques have various limitations in terms of imaging sensitivity, field of view, flow angle dependence, and imaging depth. In this study, we developed an ultrasound imaging velocimetry approach capable of visualising and quantifying dynamic flow, by combining high-frame-rate plane wave ultrasound imaging, microbubble contrast agents, pulse inversion contrast imaging and speckle image tracking algorithms. The system was initially evaluated in vitro on both straight and carotid-mimicking vessels with steady and pulsatile flows and in vivo in the rabbit aorta. Colour and spectral Doppler measurements were also made. Initial flow mapping results were compared with theoretical prediction and reference Doppler measurements and indicate the potential of the new system as a highly sensitive, accurate, angle-independent and full field-of-view velocity mapping tool capable of tracking and quantifying fast and dynamic flows.     

High flow velocity across a complicated atrial septal defect: Doppler findings and hemodynamic correlations

An unusually high atrial shunt flow velocity pattern was recorded in a patient whose atrial septal defect was created iatrogenically during a transatrial septal approach to aortic valvuloplasty. The flow velocity pattern measured by Doppler echocardiography was predictive of the high transatrial pressure gradient noted later at catheterization.     

婴幼儿房间交通的彩色多普勒诊断

目的探讨新生儿、幼儿卵圆孔未闭的血流动力学变化。方法应用ＡＣＵＳＯＮ１２８彩超仪检测卵圆孔有左向右分流者６０例;卵圆孔无分流,但先天性心脏病修补术中发现卵圆孔未闭者３１例。观察其卵圆孔瓣膜的运动和心房水平分流时相、方向、速度及分流束的宽度。结果①卵圆孔瓣膜随心动周期不同时相左右运动,似活瓣样;②４４例分流束小于５ｍｍ,多普勒频谱为双峰、正向持续性,峰速度小于０．５ｍ／ｓ;③１６例分流束大于６ｍｍ,多普勒为正向宽频谱,从收缩晚期持续至舒张期,峰速度大于０．６ｍ／ｓ;④手术组卵圆孔内径２～６ｍｍ,平均３．４ｍｍ。结论卵圆孔活瓣允许双向分流,新生儿、婴幼儿卵圆孔未闭主要表现为左向右分流。当分流束大于６ｍｍ,峰速度大于０．６ｍ／ｓ时应考虑房间隔缺损。     

组织多普勒成像评价房缺封堵术前后右心功能

目的应用组织多普勒成像(TDI)评价房间隔缺损(ASD)封堵术前后右心室心肌长轴功能变化。方法选择18例行Amplatzer封堵术的房间隔缺损患者,应用组织多普勒成像技术记录并测量右室侧壁基底段和中间段射血期、舒张早期和舒张晚期心肌运动的峰值速度(Sm,Em,Am)、收缩期位移(DS)、射血期平均加速度(Acc)等;在二维模式下测量左、右心室舒张末期横径(LV、RV)和左、右心房收缩末期横径(LA、RA)、并计算RV/LV比值和RA/LA比值。结果与术前比较,RA、RV、RA/LA、RV/LV在术后显著减小(P0.01):术后右室侧壁基底段Sm、Acc和DS比术前减低,并具有显著性差异(P0.01)。结论右室侧壁基底段Sm、Acc和DS测值可作为评价右室收缩功能改善的有效指标。     

Echocardiographic and hemodynamic characteristics of atrial septal defects created by percutaneous valvuloplasty

Twenty-nine patients were studied by pulsed, continuous wave, and color Doppler before and after percutaneous transseptal valvuloplasty. New atrial septal defects were detected in 14 patients, and the patients were monitored for up to 320 days after the procedure. The diameter of the defect, best evaluated by the transesophageal approach, was 3 to 15 mm. A narrow, high velocity (1.4 to 3.1 meters per second) left-to-right shunt jet was detected in 13 of 14 patients. The shunt jet was continuous in nine of 14 patients, late systolic-holodiastolic in four patients, and bidirectional in one patient. Cardiac catheterization in nine patients confirmed the Doppler findings and demonstrated a peak pressure gradient of 10 to 32 mm Hg between the left and right atria. Oximetry revealed a calculated pulmonary to systemic flow ratio ranging from 2.3:1 in the patient with the largest atrial septal defect by echocardiography to 1:1 (no oxygen saturation step-up) in the patient with the smallest atrial septal defect. In the three patients who underwent cardiac surgery, the operative findings confirmed those of echocardiography. We concluded that atrial septal defects are common after transseptal valvuloplasty. Usually, their relatively small size and the underlying valvular disease that produces high left atrial pressure are responsible for the high pressure gradient between the left and right atria. This results in the high velocity and continuous shunt jet detected by Doppler echocardiography.     

多发房间隔缺损经胸超声心动图与经食管超声心动图对比研究

目的 探讨经胸超声心动图(TTE)与经食管超声心动图(TEE)对多发继发孔房间隔缺损(MASD)的诊断价值.方法 应用TTE检查40例MASD,33例行TEE检查,30例行心导管检查,28例行MASD封堵术介入治疗,24例封堵成功,10例开胸体外循环下MASD修补治疗.结果 TTE与TEE全部诊断继发孔房间隔缺损,TTE诊断缺损数量准确率60%(24/40);TEE诊断缺损数量准确率97%(32/33).MASD的彩色多普勒血流显像(CDFI)特征性改变是显示多束过房间隔左向右五彩镶嵌分流束血流信号,似"漏勺样"改变,称CDFI"漏勺征".结论 TTE对MASD诊断有一定难度,TEE有特异性诊断价值.MASD开胸修补治疗行TTE检查即可,封堵术介入治疗必需行TEE检查,明确诊断缺损的数量和位置.     

Combined Vector Velocity and Spectral Doppler Imaging for Improved Imaging of Complex Blood Flow in the Carotid Arteries

Color flow imaging and pulsed wave (PW) Doppler are important diagnostic tools in the examination of patients with carotid artery disease. However, measurement of the true peak systolic velocity is dependent on sample volume placement and the operator's ability to provide an educated guess of the flow direction. Using plane wave transmissions and a duplex imaging scheme, we present an all-in-one modality that provides both vector velocity and spectral Doppler imaging from one acquisition, in addition to separate B-mode images of sufficient quality. The vector Doppler information was used to provide automatically calibrated (angle-corrected) PW Doppler spectra at every image point. It was demonstrated that the combined information can be used to generate spatial maps of the peak systolic velocity, highlighting regions of high velocity and the extent of the stenotic region, which could be used to automate work flow as well as improve the accuracy of measurement of true peak systolic velocity. The modality was tested in a small group (N = 12) of patients with carotid artery disease. PW Doppler, vector velocity and B-mode images could successfully be obtained from a single recording for all patients with a body mass index ranging from 21 to 31 and a carotid depth ranging from 16 to 28 mm.     

肌部室间隔缺损彩色多普勒超声心动图图像特征及规律性研究

目的：探讨肌部室间隔缺损（MVSD）彩色多普勒超声心动图（CDE）图像特征及规律性。方法：应用CDE对12例MVSD进行检查,寻找MVSD图像特征及规律性,10例经心血管造影对照。8例经手术证实。结果;根据CDE图像特征对11例MVSD作出正确诊断,MVSD的CDE图像特征及规律性明显;MVSD孔多、位置变化大;常合并多种畸形;部分患者手术后彩色多普勒血流显像仍可显示过室间隔残余分流束血流信号。结论：MVSD的CDE图像特征及规律性明显,CDE对MVSD有特异性诊断价值。